Motor generator circuit for outboard motors



June 27, 1933. A. E. DOMAN MOTOR GENERATOR CIRCUITFOR OUTBOARD MOTORS Filed June 10, 1950 .2 Sheets-Sheet 1 vvron BY v MVM rro New;`

Wi rNEss www June 27, 1933. A. E. DoMAN i l MOTOR GENERATOR CIRCUIT FOR OUTBOAHD MOTORS Filed June 11o, 195o 2 Sheets-Shee'cI 2 vENraR TUREYS Patented June 27, 1933 UNITED STATES PATENT oEFicE ALBERT E. DOMAN, OF SYRACU SE, NEW YORK, SSIGNOR T0 OWEN-DYNETO CORPORA- TION, OF SYRACUSE, NEW YORK, A CORPORATION 0F NEW YORK n MOTOR GENERATOR CIRCUIT FOR AOUTBOARD MOTORS Application led June 1 0,

This invention relates toan electric starter system for outboard motors of the internal combustion engine type involving the use o f a motor-generator of the third-brush type receiving current from a storage battery and operatively connected to the crankshaft of the engine coaxial therewith for starting the engine, charging the battery and otherpurposes, as set forth in my pending joint application, Serial No. 491,492 filed October 27, 1930, but refers more particularly to the several circuits of the battery and generator and their relation to each other.

The main object is to combine these circuits in a simple and ecient system of electrical distribution for startin outboard motors in which the motor circuit, generator circuit and ignition circuit are all under control of a single manually operated switch.

Another object is to provide specific means for -automatically regulating the voltage output of the variable speed engine-driven generator, so vas to prevent overcharging of the battery or, inversely, to utilize any excess charge or excess discharge of the battery for the automatic operation of the voltage regulator.

011e of the speciiicv objects is to 'provide electro-therniostatic means controlled by the voltage in the charging circuit forcutting an electric resistance into and out of the thirdbrush circuit of the motor-generator, as a partof the voltage regulating means.

Another specific object is to provide thermostatic/ means for preventing the openingof the thermostatic switch under temperatures of the ambientatmosphere.

Other objects and uses will be brought out in the following description.

In the drawings :e

Figure 1 is a vertical sectional view of the upper portion of an outboard motor .equipped with my improved electric starting system. A

Figure 2 is an enlarged horizontal sectional view taken on line v2'2, Figure 1, showing the major parts of the electric starting system in top plan.

Figure 3i's a diagrammatic view of the 1930. .serial No. 160,213.

electric starting system and the several circuits therefor.

This electric starter system is adapted to be used in connection with an outboard motor of the internal combustion engine type similar to that set forth in my pending application referred to, in that it involves the use of a motor generator A of the thirdbrush type having its field' section -a-- releasably secured to the top wall of the crankcase coaxial with the crank-shaft -C- of the engine, and a flywheel armature section -areleasably connected to said crankshaft to rotate therewith within the field section -athrough the medium of an adaptor coupling.

'The armature section -ais provided with a commutator -1- engaged by main brushes -2- and -3 and a third brush `4 mounted respectively in separate holders -2-, -3- and -4.- which, in turn, are secured to a horizontal supporting plate -5-, the latter being releasably secured to the upper marginal ed e of the cupshaped field section -aas s own in Figures l and 2.

.The iron field section -ais provided with laminated pole pieces -6, each surrounded by a series winding -7-, and a shunt winding -8 connected respectively in the main armature circuit through the medium of the brushes -2-4- and -3- and in the shunt circuit through the third brush -4- and main brush -3-, as shown more clearly in ligure 3, the main circuit and shunt circuit being provided respectively with terminal contacts -9- and -9-- of an electric switch -S- having a normally open switch member -10- movable into contact with the terminals -9- and -9- for simultaneously closing both circuits.

The switch -S- is also utilized to control a suitable ignition system I for igniting the-explosive mixture of the internal combustion engine -E The ignition system includes a spark-coil. M-, a circuit breal'rer or distributor --l\T- and a switch terminal -11- both in the primary circuit 7nand spark-plugs -oin the second-` ary circuit -0.

The switch terminal -11 is arranged in the path of the switch member 10 to be engaged thereby when the latter is moved into vengagement with the terminals and -9 for closing the primary ign1t1on vcircuit -mand thereby energizing the spark-plugs slightly in advance of the closing of the motor circuits.

A storage battery -12- is connected across the main circuit of the motor-generator for supplying current thereto when the latter is used as a starter for the engine, and also to receive current therefrom, when the starter is acting as a generator, for charging the battery and also for supplying current tothe ignition system and other trans- .engine and causing the latterA to operate under its own power, and thereby to cause the motor-generator to supply current for charging the .battery in' addition to supplying current to the shunt circuit and to the ignition system, particularly in case the batand there tery should fail to properly function, under whichconditions the engine could be started by means ofl a cranking wheel not shown.

The means for automatically regulating the voltage output of the motor-generator y preventing an excesive charging rate to the battery -12-, comprises an electrical resistance -R- and an electro-thermostatic switch 13 both connected in the shunt or third brush circuit -14-, and a voltage coil l5- which is connected across the main circuits of the generator ,-A- and battery -12- in such manner that an excess voltage in said circuits will heat the coil 15 and thereby open the thermostatic switch 15 to cut in the resistance R- in the shunt circuit -14-, the effect of which is to reduce the voltage output of the enerator and thus prevent overcharging o the battery.

The regulator switch -13- includes a thermostatic bar -13 around which the voltage coil -15- is wound to transfer its heat thereto but inclimates of widely varying atmospheric temperatures, it has been found that when such temperature exceeds a predetermined degree, it is more or less liable to prematurely open the switch -13- and thus prevent a proper voltage output of the generator for battery charging and other purposes unless some means is provided to counteract such liability.

In order to avoid this premature opening of the switch, an additional thermostatic bar -113- as s own in Figure 3, which is similar to that set forth in my Patent No. 1,498,- O77, issued June 17, 1924, or as shown in Figure 2, which is similar to that set forth in my pending application, Serial No. 341,425 iled February 20, 1929, both bars being mounted pheric temperatures, tends to deflect in theV `opposite direction against an adjustable stop -17- thus placing the bar under more or less spring tensionl which serves to yieldingly hold the switch bar -13- in its closed positioi until opened by the heat ofthe voltage coi -15-.

The compensating bar -16- shown in Figure 2, is arranged in V-shaped relation to the bar -13--and is adapted to deflect in the' same direction as the bar -13-, under engine and flywheel armature section -a as shown more clearly in Figure 2.

When the switch member -S- is closed on the terminals -11 9 and -9-, the current from the battery -k-B-T will flow through the ignitionv system and return vfor igniting the combustible mixture, -while at the same time, a part of the battery is free to flow through the series winding ,7- of the motor-generator circuit for operating the latter to start the engine.

When the engine is running under Aits own power and thereby operating the motor-gen'- erator, the current from the. generator may pass through the series winding -7, closed switch 1S- and thence through the ignition system and return to supply current to the engine independently of the battery in case the latter should fail to properly function, while a part of the generator current 0f the third-brush circuit 14,- to effect i..

partial automatic regulation of the voltage output, as previously described.

It will also be noted that a part of the generator current may pass from the brush -2- through the'voltage coil -15- and return so that in case the voltage exceeds that required for properly charging the battery and other purposes, the voltage coil will become heated and the heat thus developed will be transferred to the thermostatic bar -13- for opening the switch 13 and thereby cutting in the resistance R as a further means for automatically regulating the voltage output of the generator.

It is evident, however, that any suitable electric ignition system may be used in connection with the electric starting system and that various changes may be made in the arrangement of the starting system, without 2 deparlting from the spirit of this invention.

c alm:

In an electric starting and ignition system for internal combustion engines, a starting-motor-generator of the third brush type having a' self closing thermostatic switch and an electricresistance connectedr in parallel in the third brush circuit, a storage battery and a voltage coil connected in parallel across the main brush circuit, said voltage coil being in heat transfer relation to the thermostatic switch for controlling the battery-charge, an ignition device connected in the battery circuit and also in the main brush circuit, and a single electric switch operable at will for controlling the battery-charging circuit, the ignition circuit, and the third brush circuit and adapted to close the ignition circuit from the battery in advance of its other circuits.

In witness whereof I have hereunto set my hand this 27 th day of Ma 1930.

. ALBERT DOMAN.. 

